<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
</head>
<style>
    body{
        margin: 0;
    }

    .background{
        height: 200px;
        background-color: black;
        position: relative;
        color: white;
    }

    .background::before{
        content: '';
        width: 100%;
        height: 100%;
        position: absolute;
        background: url("/src/img/css3/下载.jfif") no-repeat center/120%;
        filter: blur(60px);
    }
</style>
<body>
    <div class="background">
        我是内容
    </div>
</body>
</html>